package com.feeyo.mpeg2ts.util;

public class TsUtil {
	
	private static final long[] crc_table = new long[] { 0x00000000, 0x04c11db7,
			0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b, 0x1a864db2,
			0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
			0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70,
			0x48d0c6c7, 0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b,
			0x569796c2, 0x52568b75, 0x6a1936c8, 0x6ed82b7f, 0x639b0da6,
			0x675a1011, 0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
			0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039, 0x8b27c03c,
			0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef,
			0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea,
			0xa06c0b5d, 0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
			0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95, 0xf23a8028,
			0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, 0xe13ef6f4, 0xe5ffeb43,
			0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0, 0x3d044b19,
			0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
			0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13,
			0x054bf6a4, 0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0,
			0x71159069, 0x75d48dde, 0x6b93dddb, 0x6f52c06c, 0x6211e6b5,
			0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
			0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba, 0xaca5c697,
			0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc,
			0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041,
			0x87ee0df6, 0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
			0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e, 0xf3b06b3b,
			0xf771768c, 0xfa325055, 0xfef34de2, 0xc6bcf05f, 0xc27dede8,
			0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34, 0xdc3abded,
			0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
			0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56,
			0x4bc510e1, 0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d,
			0x558240e4, 0x51435d53, 0x251d3b9e, 0x21dc2629, 0x2c9f00f0,
			0x285e1d47, 0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
			0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff, 0x1011a0fa,
			0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9,
			0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc,
			0xef68060b, 0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
			0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3, 0xbd3e8d7e,
			0xb9ff90c9, 0xb4bcb610, 0xb07daba7, 0xae3afba2, 0xaafbe615,
			0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71, 0x92b45ba8,
			0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
			0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645,
			0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096,
			0x7200464f, 0x76c15bf8, 0x68860bfd, 0x6c47164a, 0x61043093,
			0x65c52d24, 0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
			0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec, 0x3793a651,
			0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a,
			0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17,
			0xc8ea00a0, 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
			0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18, 0xf0a5bd1d,
			0xf464a0aa, 0xf9278673, 0xfde69bc4, 0x89b8fd09, 0x8d79e0be,
			0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662, 0x933eb0bb,
			0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
			0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4 };
	
	public static long mpegts_crc32(byte[] data, int offset, int len) {
		long crc = 0xffffffff;
		for (int i = 0; i < len; i++) {
			int pos = (int) ((crc >> 24) ^ data[i + offset]) & 0xff;
			crc = (crc << 8) ^ crc_table[pos];
		}

		return crc;
	}
	
	public static byte[] margeByteArray(byte[] a, byte[] b) {
		
		if ( a == null ) {
			return b;
		}

		byte[] buf = new byte[a.length + b.length];
		System.arraycopy(a, 0, buf, 0, a.length);
		System.arraycopy(b, 0, buf, a.length, b.length);

		return buf;
	}
	
	public static String hexString(byte[] bytes, int offset, int length) {
        StringBuilder sb = new StringBuilder();
        sb.append("    ");
        for (int i = offset; i < offset + length; i++) {
        	
        	sb.append( String.format("%02x", bytes[i]) ).append(" ");
            //sb.append("0x").append( String.format("%02x", bytes[i]) ).append(" ");
            if ((i + 1) % 32 == 0) {
                sb.append("\r\n    ");
            } 
        }
        return sb.toString();
    }

}
